Importance of carbs when running

When it comes to fueling the body, carbs are important macronutrients.

Carbohydrates give us a quick source of energy, allowing us to perform at our highest intensity. However, our stores of carbs are limited. In order to maintain high levels of intensity when training for longer time periods, we need to continually replenish these stores to avoid running low. Planning your carb intake both before and after exercise is also vital for your performance and recovery.

1. You need carbs to perform

During high-intensity workouts, the body uses carbs as its primary fuel. Carbs are stored in muscles and the liver in the form of glycogen. However, they need to be replaced regularly since these stores are limited and deplete quickly. Fat is also used as fuel, but it takes longer for the body to extract energy from it compared to carbs. As a result, fat is mainly used for low-intensity activities.(1) 

Carbohydrates are vital for runners to consume, for all the reasons stated above. It’s all about choosing the right carbohydrate sources to match your workout’s duration and intensity. There are different kinds of carbs, including simple and complex.

Simple carbs: digested quickly, providing a rapid source of energy. This makes them suitable to eat before your run to provide the body with energy. Yet they are also needed after the run, to quickly replenish the empty glycogen stores for a more efficient recovery. (2)

Examples of simple carbs: bananas, potato, white rice, raisins, rice cakes, jam, juice and white bread. 

Complex carbs: offer a longer-lasting source of energy, and should be included in meals that aren’t directly before or after your run. These types of carbs are higher in dietary fiber which makes them more filling. They take longer to digest, are important for your intestinal flora and contribute higher nutritional value when compared to simple carbs. (3) However, eating high-fiber complex carbs too close to workouts can cause stomach and intestinal problems. (1)

Examples of complex carbs: whole grain bread, brown rice, beans, lentils, crispbread, vegetables, and oats. 

Carbohydrate sources such as whole-grain products can potentially be too filling for runners. When following a high-energy diet during training, it can be difficult to get the carbohydrates needed for adequate performance because complex carbs make you feel full very quickly. Pasta or white rice, on the other hand, provide a larger amount of carbs per 100g and would, therefore, be better food choices when you’re in need of a high volume of carbohydrates. (1)

2. How many carbs should you eat

Your required daily intake of carbs depends on the intensity of your workout. When performing moderate to intensive workouts, a daily intake of 8-10 grams per kg (3.5 – 4.5 grams per lb) of body weight is recommended. If you’re engaging in high-intensity workouts lasting for several hours, the daily recommended intake is 12 grams of carbohydrates per kg (5.5 grams per lb) of body weight. (4) It’s easier to reach the recommended amount when you include sources of carbohydrates in every meal, like oats, pasta, potato, bread, and rice. It can also be helpful to use a tracking tool to make sure you’re reaching these recommendations. To reach the recommended amounts of carbs for a 150-lb woman with a moderate to intensive training schedule and an overall energy requirement of 2000 kcal per day, the daily intake could look like:

Breakfast: oatmeal, two slices of wheat bread with cream cheese, one banana

Lunch: pasta with tofu sauce and a piece of fruit

Snack: smoothie and a slice of banana bread with topping

Dinner: white rice with fish and sauce

Snack: yogurt with granola and fruit 

This would add up to around 550 grams of carbohydrates altogether, meeting the requirements of a 150-lb woman performing moderate to intensive workouts.

3. Carbs before and after training

Carbs are important before training, but it’s important to get them in after the workout too. The muscles have a greater capacity to store carbohydrates after a workout and this replenishes glycogen stores in a more effective way. This is important, as glycogen stores will be empty after a hard running session. If you’re planning to work out again during the same day, it’s even more important to fill up these stores before you begin the next session. Otherwise, your body won’t have enough energy to perform. (2)(3) It is recommended to take in at least 1-1.2 grams of carbohydrates per kg (0.5 – 0.6g per lb) of body weight an hour after completing the workout. When replenishing the body’s glycogen stores after a workout, the amounts of carbohydrates are more important than their source. If the next workout is taking place soon, it is better to eat simple carbs since the body absorbs those carbohydrates quicker. (4)

3. Why is banana bread a good workout food choice?

Bananas are a great carb source, and banana bread can, therefore, be a great pre- or post-workout snack! It’s portable, making it the perfect snack on the go! An extra benefit is that bananas are filled with potassium which is important for nerve and muscle functions in the body, as well as for regulating the blood pressure. (5) Try this delicious banana bread recipe- we promise that you won’t be disappointed!

Banana bread

266 kcal, 60 min, 8 servings

4 bananas

1 cup / 4.4 oz old fashioned rolled oats (125g)

1 cup / 3.2 oz flour (90g)

2 eggs

1 tsp ground cinnamon

½ tsp ground cardamom

1 tsp salt

1 tsp of baking soda

½ cup / 120 ml unsweetened plant-based milk

¼ cup / 2.1 oz honey (60g)

½ cup / 2.9 oz chopped nuts (82g)

1 tbsp coconut oil


1. Set the oven to 350°F / 175°C.

2. Mix the oats and flour with a blender or with a stick blender. Add 3 bananas and the eggs, mix until combined.

3. Pour mixture into a bowl, add the rest of the ingredients except the coconut oil and the remaining banana and blend well.

4. Grease a 9×5-inch (23×13 cm) loaf pan with coconut oil.

5. Pour batter into the loaf pan, cut the remaining banana in half and place on top of the mixture. Bake in preheated oven for 45 minutes.

6. Let the bread cool in the loaf pan for 10 minutes, then transfer it to a
wire rack to cool for 20 minutes before slicing.


1. Sveriges Olympiska Kommitté/SOK. Kostrekommendationer för olympiska idrottare. 2016.

2. Burke, L., Deakin, V. Clinical Sports Nutrition. 5th ed. New York; 353-355.

3. Burke, L., Deakin, V. Clinical Sports Nutrition. 5th ed. New York; 370-390.

4. Andersson, A. Idrottsnutrition. I Näringslära för högskolan, Abrahamsson, L., Andersson, A., Nilsson, G (red.),160-179. Stockholm: Liber AB, 2013.

5. Livsmedelsverket. Kalium. 2020-01-27.

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